Hey guys! I cannot figure this out, may i have some help?

18m
=
m - 19m

1. judy took $30 with her to spend on popcorn and drinks for herself and her friends at the movie theater. the price for each bag of popcorn was $5. the price of each drink was half the price of a bag of popcorn. (a) sketch the graph that represents the situation and label the intercepts. use one axis to represent the number of bags of popcorn and the other axis to represent the number of drinks. (b) explain your graph.